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  <script>

    // Math.random(): [0, 1)
    for (var i = 0; i < 1000; i++) {
      var randomNum = Math.random() * 100 // 99
      randomNum = Math.floor(randomNum)
      console.log(randomNum)
    }

    // 生成一个0~99的随机数
    var randomNum = Math.floor(Math.random() * 100)

  </script>

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